feat: add models for physical files, policies, and user management

- Implement PhysicalFile model to manage physical file references and reference counting.
- Create Policy model with associated options and group links for storage policies.
- Introduce Redeem and Report models for handling redeem codes and reports.
- Add Settings model for site configuration and user settings management.
- Develop Share model for sharing objects with unique codes and associated metadata.
- Implement SourceLink model for managing download links associated with objects.
- Create StoragePack model for managing user storage packages.
- Add Tag model for user-defined tags with manual and automatic types.
- Implement Task model for managing background tasks with status tracking.
- Develop User model with comprehensive user management features including authentication.
- Introduce UserAuthn model for managing WebAuthn credentials.
- Create WebDAV model for managing WebDAV accounts associated with users.

sqlmodels/node.py

@@ -0,0 +1,103 @@
+from enum import StrEnum
+from typing import TYPE_CHECKING
+
+from sqlmodel import Field, Relationship, text, Index
+
+from .base import SQLModelBase
+from .mixin import TableBaseMixin
+
+if TYPE_CHECKING:
+    from .download import Download
+
+
+class NodeStatus(StrEnum):
+    """节点状态枚举"""
+    ONLINE = "online"
+    """正常"""
+    OFFLINE = "offline"
+    """离线"""
+
+
+class NodeType(StrEnum):
+    """节点类型枚举"""
+    MASTER = "master"
+    """主节点"""
+    SLAVE = "slave"
+    """从节点"""
+
+
+class Aria2ConfigurationBase(SQLModelBase):
+    """Aria2配置基础模型"""
+
+    rpc_url: str | None = Field(default=None, max_length=255)
+    """RPC地址"""
+
+    rpc_secret: str | None = None
+    """RPC密钥"""
+
+    temp_path: str | None = Field(default=None, max_length=255)
+    """临时下载路径"""
+
+    max_concurrent: int = Field(default=5, ge=1, le=50)
+    """最大并发数"""
+
+    timeout: int = Field(default=300, ge=1)
+    """请求超时时间（秒）"""
+
+
+class Aria2Configuration(Aria2ConfigurationBase, TableBaseMixin):
+    """Aria2配置模型（与Node一对一关联）"""
+
+    node_id: int = Field(
+        foreign_key="node.id",
+        unique=True,
+        index=True,
+        ondelete="CASCADE"
+    )
+    """关联的节点ID"""
+
+    # 反向关系
+    node: "Node" = Relationship(back_populates="aria2_config")
+    """关联的节点"""
+
+
+class Node(SQLModelBase, TableBaseMixin):
+    """节点模型"""
+
+    __table_args__ = (
+        Index("ix_node_status", "status"),
+    )
+
+    status: NodeStatus = Field(default=NodeStatus.ONLINE)
+    """节点状态"""
+
+    name: str = Field(max_length=255, unique=True)
+    """节点名称"""
+
+    type: NodeType
+    """节点类型"""
+
+    server: str = Field(max_length=255)
+    """节点地址（IP或域名）"""
+
+    slave_key: str | None = Field(default=None, max_length=255)
+    """从机通讯密钥"""
+
+    master_key: str | None = Field(default=None, max_length=255)
+    """主机通讯密钥"""
+
+    aria2_enabled: bool = False
+    """是否启用Aria2"""
+
+    rank: int = 0
+    """节点排序权重"""
+
+    # 关系
+    aria2_config: Aria2Configuration | None = Relationship(
+        back_populates="node",
+        sa_relationship_kwargs={"uselist": False, "cascade": "all, delete-orphan"},
+    )
+    """Aria2配置"""
+
+    downloads: list["Download"] = Relationship(back_populates="node")
+    """该节点的下载任务"""